A diver from Hinckley has died after getting into trouble while exploring a dry cave in a disused quarry in north Wales.

Will Smith, 40, was with two friends on Saturday at Aber Las in the Glyn Ceiriog valley when he was overcome by poisonous gas in the sump hole and slipped back down a slope into the water.

His companions’ attempts to resuscitate him were in vain and they raised the alarm at around 1.50pm, after having to leave the scene.

A specialist search and rescue mission was launched and Mr Smith’s body was recovered early on Sunday morning.

Czech-born Sasha London who was with Mr Smith on the caving expedition, said: “Aber Las is a former slate mine which we had been investigating for about a year and a half. We’d go there every month or so and just explore a bit more each time.

“For this visit one of the objectives was to have a look at a dry passage around 1,000ft into the flooded mine. Will went into the passage while I and our other friend waited for him just on the edge. We could see him, he turned around and my friend heard him say something about having a problem with gas, then he tumbled down the slope into the water. We tried to revive him but he wasn’t breathing.”

The trio were members of the UK Mine/Cave Diving and Exploration group which organises cave diving trips around the UK.

Mr London said he and Mr Smith had dived together in France and were among a number planning an ambitious trip to Mexico before this unforseen and devastating accident.

A former John Cleveland College student who ran wall and floor tiling business, WS Tiles, Mr Smith leaves wife, Kelly and two daughters.

Friend, Geoff Aldridge who was best man at his wedding, said: “He was one of the most honest blokes you could meet. He had the time of day for everyone and was genuinely interested in how people were doing.”

Builder, Mr Aldridge said he wished he could have dived alongside his former schoolpal to share in the joy and wonder it brought him.

“I know diving became very important to Will,” said Mr Aldridge. “He was trained by the best and was meticulous with his safety. He was also an inspiration to up and coming divers so I understand.

“But he was very much like that, focused, with an appetite for life, whatever he was involved in he gave it his all and he loved the great outdoors. This has been such a massive shock to everyone. People have said he had the biggest smile ever and we are all going to miss that.”

Before taking up diving Mr Smith had been a well-known character on the amateur boxing scene, fighting and coaching for the Heart of England Community Boxing Club.

A post on the Burbage-based club’s Facebook page read: “Very sad to report the death of Will Smith. Newer members will not remember Will.

"He was a committed, tough and strong amateur boxer who engaged in around 35 contests. He was a level II coach and a key member of our coaching team for several years. Recently he has not been involved in boxing but had become a very enthusiastic scuba diver and into ‘cave diving’. Unfortunately he lost his life while cave diving at the weekend. It was a pleasure to coach Will and it was a pleasure to work alongside him as a coach. He was a good friend and you will struggle to find anyone who had a bad word for him. RIP Will.”

Diver, Paul Rosendale posting on the Facebook page of a fellow UK Mine/Cave Diving and Exploration member, said: “First class chap, everyone’s friend, awesome diver, devoted husband and father. Just a few to sum up Will Smith.”

A Sea King helicopter, dozens of volunteers and cave rescue teams were involved in the search for Mr Smith’s body. The north Wales coroner is expected to open an inquest next week.